package com.tao.common.utils;

import java.security.MessageDigest;

public class MD5Util {

    static  final  String SALT ="1234567#1&afgfhasijf";

    /***
     * MD5加密 生成32位md5码
     *
     * @param inStr 待加密字符串
     * @return 返回32位md5码
     */
    public static String md5Encode(String inStr) throws Exception {
        MessageDigest md5 = null;
        try {
            md5 = MessageDigest.getInstance("MD5");
        } catch (Exception e) {
            System.out.println(e.toString());
            e.printStackTrace();
            return "";
        }

        byte[] byteArray = inStr.getBytes("UTF-8");
        byte[] md5Bytes = md5.digest(byteArray);
        StringBuffer hexValue = new StringBuffer();
        for (int i = 0; i < md5Bytes.length; i++) {
            int val = ((int) md5Bytes[i]) & 0xff;
            if (val < 16) {
                hexValue.append("0");
            }
            hexValue.append(Integer.toHexString(val));
        }
        return hexValue.toString();
    }
    //加盐加密
    public static String mdSalt(String a) throws Exception {
        return md5Encode(a+SALT);
    }

    //加盐加次数
    public static String md5ci(String a,int num)  {
        try {
            if( num == 1){
                return mdSalt(a);
            }
            return mdSalt(md5ci(a,num-1));
        }catch (Exception e){
            e.printStackTrace();
            return null;
        }

//        if( num == 2){
//            return mdSalt(mdSalt(a)); //mdSalt(a)  == md5ci(a,1)
//        }
//        if( num == 3){
//            return mdSalt(mdSalt(mdSalt(a))); //mdSalt(mdSalt(a))  == md5ci(a,2)
//        }
//        if( num == 4){
//            return mdSalt(mdSalt(mdSalt(mdSalt(a))));//mdSalt(mdSalt(mdSalt(a)))  == md5ci(a,3)
//        }
    }


    /**
     *测试
     * @throws Exception
     */
    public static void main(String[] args) throws Exception {
        // 加密 加次数  加盐
        String a = "123456";

        System.out.println(mdSalt(mdSalt(mdSalt(a))));
        System.out.println(md5ci(a,3));
    }

}
